Kentwan Balmer was cagey about whether he was 100 percent healthy Monday, saying that percentages don”t matter once you hit the field.

But 100 percent happy?

“There”s no doubt about that,” Balmer said.

The former first-round pick was all smiles after trying to bang his way back up the depth chart. The 49ers held their first two-a-day practice session of training camp and Balmer worked so hard that he spent much of an interview chugging water from a large container.

Balmer didn”t get to work up such a sweat during off-season minicamps. He kept away from the field by a training staff that wanted to be smart about his comeback from a shoulder injury.

But Balmer is a man in a hurry these days. He”s long overdue to make an impact in the NFL, having contributed next to nothing over his first two seasons.

The 29th overall pick in 2008, Balmer has zero career starts, zero career sacks and only a handful of tackles.

Now, as the hype fades, he”s just another guy fighting for playing time.

“Every year you have to prove yourself. I don”t care where you were drafted at,” Balmer said. “You want to go out there and show people what you can do.

“People always harp on, ”First-round pick this, first-round pick that.” Yeah, I”m more than blessed to be a first-round pick. I”m happy. But at the same time, this is the NFL. There are a lot of first-round picks out there.”

Balmer, a gregarious native of Weldon, N.C., called being back on the field his “therapy” and said “nothing makes him happier” than being able to feel like part of the team again.

It”s been a long road back. After sustaining a season-ending shoulder injury last Nov. 29, Balmer”s rehabilitation has been just as frustrating as the rest of his career. He joked Monday about how often he clashed with the team”s training staff, always wanting to push the limits while the doctors urged caution.

“Those were good conversations,” he said, tongue in cheek. “They were, um, spirited. That”s a better word. ”Spirited.” Very ”spirited.””

Turned loose for training camp, Balmer enters this season as a backup at left end and right end. Listed at 6-foot-5, 315 pounds, he is also capable of filling in at nose tackle.

Balmer concedes it”s been a rough transition to the NFL after a standout career at North Carolina. Among his supporters is defensive coordinator Greg Manusky, who says often that the transition from college to the pros is brutal on defensive lineman.

Balmer agreed. He said it was especially tough to go from a 4-3 scheme with the Tar Heels to a 3-4 scheme with the 49ers.

“Defensive line isn”t a cake position. I can”t go out there and do what (receiver) Michael Crabtree does,” he said. “I have to worry about Larry Allen or Eric Heitmann coming at me every day, sometimes together. You can”t prepare for that in college, you know what I”m saying?”

But he said he”s ready to make an impact. In fact, Balmer indicated that he”s been ready for a while.

Asked if whether he was ready for a bigger role before getting hurt last season, Balmer smiled wide and began to stall. He asked to hear the question again and again then pleaded with teammate Ricky Jean Francois to help him craft a diplomatic response.

“Honestly. Honestly. I have to be truthful. I just felt likeÉ God! I felt like I was ready. I mean, I felt like I had a good preseason. But it isn”t up to me who gets an opportunity, you know what I”m saying? I felt like I was ready, but obviously that wasn”t the case. You turn on the preseason film and you make your own judgment.”

Though he grew up in North Carolina, Balmer was a 49ers fan. He was 8 years old when he watched the 49ers” goal-line stand against Natrone Means and the San Diego Chargers in Super Bowl XXIX.

His dad, he said, “is the biggest 49ers fan you”ll ever meet.”

So he understands the desire to return the team to its former glory. And he wants to be on the field when it happens.

“This year, I”m always putting it on the line. I”m going go out there and do the best I can,” Balmer said. “Like I said, the decision of who plays isn”t mine. Just go out there and be ready when I get my opportunities.”